Light activated sequential switching mechanism

ABSTRACT

A light actuated sequential switching mechanism for applying an energizing pulse in a predetermined order to each injector in an electronic fuel injection system on an internal combustion engine. A single source of radiant energy is sequentially applied to a plurality of radiant energy activating switching members each controlling the activation means of a fuel injector. A fiber optic conducting member &#39;&#39;&#39;&#39;pipes&#39;&#39;&#39;&#39; the radiant energy from the source to each switching member. The rotation of the distributor timing shaft provides the firing synchronism between the injector and the operation of the internal combustion engine.

United States Patent Keely et al.

LIGHT ACTIVATED SEQUENTIAL SWITCHING MECHANISM 3,587,535 6/1971Kimberley et al. 123/32 AE 3,621,826 11/1971 Chrestensen 123/148 E3,767,935 10/1973 .Trass 123/148 E X [75] Inventors: William ArthurKeely, Highland,

2 t Mgrle Manford Kreger Primary ExaminerCharles J. Myhre l AssistantExaminer -Tony Argenbright [73] Assignee: The Bendix Corporation,Southfield, Attorney, Agent, or FirmRussel C. Wells Mich.

[22] Filed: June 17, 1974 [57] ABSTRACT [21] App1.No.: 480,061 A lightactuated sequential switching mechanism for applying an energizing pulsein a predetermined order to each injector in an electronic fuelinjection system 5 123/32 5 on an internal combustion engine. A singlesource of radiant energy is sequentially applied to a plurality of [58]Fleld of Search i iZ g radiant energy activating switching members eachcontrolling the activation means of a fuel injector. A fiber opticconducting member pipes the radiant en- [56] References Clted ergy fromthe source to each switching member. The

UNITED STATES PATENTS rotation of the distributor timing shaft providesthe fir- 3,l63,700 12/1964 Williamson 88/225 ing synchronism between theinjector and the opera- 3,365,58O 1/1968 Cannella 250/227 {ion of theinterna] combustion engine, 3,438,362 4/1969 Clyborne et a1. 123/146.5 A3,463,134 8/1969 Zechnall et a1. 123/146.5 A 10 Claims, 6 DrawingFigures L IGNITION -5 SYSTEM r Q //////z// -:w =-42 30 32 24 v: \\;m /Z

I r: l 2 20 I 1 I UEL INTERNAL INJECTOR COMBUSTION /6 CONTROL ENGINELIGHT ACTIVATEDSEQUENTIAL SWITCHING MECHANISM BACKGROUND OF INVENTION 1.Field of the Invention This invention relates to electromechanicaltriggering mechanisms in general and more particularly to light actuatedswitching systems using light conducting rods for use in a fuelinjection equipped internal combustion engine.

2. Description of the Prior Art Several devices utilizing sources ofillumination energy and photo responsive members are found in thedistributor art of internal combustion engines. Many have a single lightsource usually placed outside of the distributor housingand a singlephoto cell also stationarily mounted The light is then piped from thesource, across a path along which one or more members move to the cell.By the movement of the members along the path, a light chopping actionis supplied to the cell.

One particular distributor system utilizes a single light source, a longcomplicated light piping system, a lens system, a movable member havinga plurality of slots moving along the path and a single photo or lightresponsive member. Both the light source and the responsive member arepositioned outside of the distributor housing and require a generallyU-shaped light piping arrangement. As the moving member passes betweenthe lens system and an open end of the light piping system, the lightenergy is removed from the light responsive member. The single memberoutput requires a further means to segregate and apply the output pulsesto various spark plugs for proper sequential operation.

Other systems utilize a rotating disc having a plurality of aperturestherein moving between a light source and a photo cell. As a result ofthe pattern of spaced apertures, a chopping light signal is transmittedto the photo cell. Since there is only one photo cell, additional meansmust be developed to separate the several pulses from the cell.

SUMMARY OF THE INVENTION It is a principal object of this invention toposition a single source of radiant energy and a plurality of radiantenergy responsive members and to distribute by means of a fiber opticbundle, the radiant energy to each responsive member in a predeterminedsequence.

It is another object of this invention to provide a breakerless highreliable pulse generating system for controlling the fuel injectors in afuel injection system.

It is a further object of this invention to reduce the complexity ofboth the mechanical and electronic members ofa reliable pulse generatingsystem by utilizing only one moving member and plurality of stationaryactivating members each respectively electrically coupled to aninjector.

These and other objects of the invention will become apparent from thefollowing drawings, detailed description and claims ofa light activatedsequential switching system for use in a fuel injection system of aninternal combustion engine. A shaft is coupled at one end for rotationwith the distributor timing shaft and has at the other end a disc memberhaving a pair of spaced broadsides. Radially extending from the centerof the disc to the periphery is alight conductingchannel of fiber opticmembers. One end of "the members is flush with the one broadside surfaceof the disc at the center thereof and opposite the shaft and the otherend of the members is flush with the other broadside of the disc andnear its periphery. A source of radiant energy is positioned oppositethe one end of the bundle and a plurality of light responsive membersare positioned to receive the radiant energy emitting from the other endof the bundle.

BRIEF DESCRIPTION OF THE DRAWINGS In the drawings FIG. 1 is a plan viewof the rotating member with several adjacent members removed forclarity;

FIG. 2 is a sectional view taken along line 2-2 of FIG. 1 with thehousing and light source shown;

FIG. 3 is a plan view of one embodiment of the printed circuit boardsupporting the light responsive members; V

FIG. 4 is another embodiment of the rotating member illustrating twofiber optic bundles; U

FIG. 5 is another embodiment illustrating the use of a redundant radiantenergy source;

FIG. 6 is a circuit for controlling the radiant energy sources of FIG.5.

DETAILED DESCRIPTION Referring to the Figs. by the characters ofreference there is illustrated in FIG. 2 in sectional form the lightactuated sequential switching mechanism 10 of the present invention. Asillustrated in FIG. 2 the switching mechanism is enclosed in a housing12 for the purposes of protecting the mechanism from dirt, grime andother foreign materials.

The mechanism comprises a shaft 14 which is coupled for rotation withthe distributor timing shaft of an internal combustion engine 16. Atessentially the free end '18 of the shaft 14 there is positioned bymeans of a pin 20 or other suitable fastening means a disc shaped member22 having a pair of spaced broadside surfaces 24 and 26. One surface 24is mounted substantially flush with the free end 18 of the shaft 14 andopposite the coupling end of the shaft 14. As indicated the disc 22 ismounted for rotation with the shaft. Spaced from and axially in linewith the free end 18 of the shaft 14 is a source of light or radiantenergy 28 which is directed toward the one broadside surface 24 of thedisc 22. Formed or molded within the disc 22 and extending between thetwo broadside surfaces 24 and 26 is a fiber optic bundle 30. One end 32of the fiber optic bundle 30 is axially in line with the radiant energysource 28. The other end 34 of the fiber optic bundle 30 is flush withthe other broadside surface 26 of the disc 22 and near the peripherythereof. Spaced from the other broadside surface 26 of the disc is asupporting means 36 for supporting a plurality of light actuatedswitching members 38 wherein each switching member 38 is sequentiallyadapted to be in line with the other end 34 of the fiber optic bundle30.

The shaft 34 of the mechanism 10 as illustrated in FIG. 2 is coupled bymeans not shown to the crankshaft of the internal combustion engine 16.In this manner the shaft 14 will rotate synchronously with the rotationof the crankshaft of the internal combustion engine 16. One such shaft14 may well be the distributor timing shaft and in a preferredembodiment of the present invention this shaft is an extension of thedistributor timing shaft. This shaft 14 is suitably journaled forrotation by well known means which are not illustrated in the Fig.

As indicated the disc shaped member 22 is secured to the shaft 14 bymeans of a collar 40 or other fastening means. In the preferredembodiment there is a concentric collar 40 having an aperture thereinfor receiving the free end 18 of the shaft 14 and in order to provide apositive rotation of the disc 22. With the shaft 14, conventionalpinning means 20 is provided for securing the disc to the shaft. Thedisc 22 is fabricated from some nonmetallic material which is capable ofbeing molded into the desired shape including the fiber optic bundle 30.The material used for the disc shaped member 22'and the method ofmanufacturing are illustrations of one form which the disc may take.

Formedwithin the disc 22 and molded thereto and extended in asubstantially radial direction from the center of the disc is the fiberoptic bundle 30. The bundle 30 comprises many strands of fiber opticmaterial and collectively they extend from the center portion of the onebroadside 24 of the disc through the disc 22 and out the other broadside26 of the disc near the periphery thereof. Thus by this configurationand in a manner well known in the art the fiber optic bundle 30 willreceive radiant energy on one side 24 of the disc 22, transmit theenergy through the disc, and have it emit from the other side 26 of thedisc. As illustrated in the plan view of FIG. 1, this fiber optic bundle30 extends in a substantially radial direction.

Referring again to FIG. 2, there is illustrated the mounting 42 andsupporting of the source of radiant energy 28 in a manner overlying theone end 32 of the fiber optic bundle 30. As illustrated in FIG. 2, thesource of radiant energy 28 is axially in line with the free end 18 ofthe shaft 14. In the preferred embodiment, the source is a light bulband enclosed in a housing 42 which may assist in directing the lightenergy from the bulb to the fiber optic bundle 30. In lieu of a lightbulb other such devices as light emitting diodes may be used underproper conditions.

Referring to FIG. 3 there is illustrated the supporting member 36 in theform of a printed circuit board which supports and maintains theplurality of light actuated switching members 38. The number ofswitching members 38 is equal in number to the number of fuel injectorsin a fuel injection control system 44 or the number of spark plugs andeach are respectively connected in electrical circuit to each of thefuel injectors. Extending from one edge 46 of the printed circuit board36 is a connector means 48 for electrically connecting the lightactuated switching members 38 to the fuel injector control 44. Since thedisc member 22 rotates about the shaft 14, the light actuated switchingmembers 38 are positioned in a circumferential spaced apart relationship concentric with the clearance hole 50 for the shaft 14 locatedin the center of the board 36. The switching members 38 are sopositioned on the board 36 and the board is so positioned in therelationship to the rotating disc shaped member 22 such that each lightactuated switching member 38 is positioned so as to receive lightemanating from the one end 34 of the fiber optic bundle 30 when that end34 and the switching member 38 are in line relative to each other.

In the preferred embodiment the source of radiant energy 28 is energizedwhenever the ignition system 51 of the internal combustion engine 16 isturned on. As the distributor shaft 14 begins to rotate, the disc shapedmember 22 also rotatesand through means of the fiber optic bundle 30transmits light energy from the radiant energy source 28 to each lightactuated switching member 38 in sequential relationship. The signalsgenerated by the light actuating switching members 38 are applied toindividual injectors in the fuel injection control system 44 of theinternal combustion engine 16.

Referring to FIG. 4 there is illustrated a modification in thepositioning of the fiber optic bundles 52 and 54 within the disc shapedmember 56. Particularly illustrated in FIG. 4 is the use of two fiberoptic bundles 52 and 54 both beginning or receiving radiant energy atthe center of the disc 56 and'transmitting the energy to the oppositeside of the disc near its periphery. With the use of two fiber opticbundles 52 and 54, as illustrated in FIG. 4, the number of lightactuated switch members 38 will be reduced accordingly. Referring toFIG. 3 and using the disc 56 of FIG. 4 every other light actuatedswitching member 38 in FIG. 3 may be removed. The angle N between eachfiber optic bundle 52 and 54 is equal to an odd multiple of the quotientfound by dividing 360 by the number of injector actuated circuits in thefuel injector control system 44 required for the particular internalcombustion engine 16. For example in an eight cylinder engine using twofiber optic bundles the angle N may be any odd multiple of the angle 45.As illustrated in FIG. 4 the angle N is approximately 135 and theangular spacing of the light actuated switching members is If such aconfiguration was used in a six cylinder engine the angle N would be 60and the angular spacing of the light actuated switching members 38 wouldbe Referring to FIG. 5 there is illustrated a modification for mountingat least two sources of radiant energy 58 and 60 in aredundant'configuration. As illustrated in FIG. 5 by the use of tworadiant energy sources this provides an insurance of one source if theother source fails. It is important in the mounting of the two sources58 and 60 within their own housing 62 that all the radiant energyemitted by either source is directed toward the receiving surface 32 ofthe fiber optic bundle 30 on the disc 22. Thus as illustrated in FIG. 5each source 58 and 60 is mounted to a surface which is slightly inclinedI toward the projected axis of the shaft 14.

Referring to FIG. 6, there is illustrated an electrical circuit 64 forcontrolling the dual radiant energy sources 58 and 60 of FIG. 5. Thecircuit of FIG. 5 is arranged so that when power is applied to thecircuit 64 the first radiant energy source 58 is energized. Thetransistor Q1 66 is turned on driving its collector near ground. Withthe collector of the transistor Q1 66 near ground the second radiantenergy source 60 is not energized. When the first radiant energy source58 burns out or is extinguished, the voltage at the junction 68 of theradiant energy source 58 and its series resistor 70 rises toward thesource voltage. This increasing voltage signal is reflected across thecapacitor 72 to the base of the transistor Q2 74 driving it intoconduction. When the transistor Q2 74 is turned on, its collectorapproaches ground, grounding the base of the transistor Q1 66, turningit off. When the transistor Q1 66 is driven out of conduction a'thesecond radiant energy source 60 is immediately energized through itsseries resistor 76 from the power source.,Subsequent turning on of thetransistor Q2 74, the source of power is supplied through the tworesistors 76 and 78 in series with the base of the transistor Q2 74thereby causing the second source of radiant energy 60 to be energized.

There is thus shown and described a light actuated sequential switchingmechanism for use in a fuel injection system. The mechanism is used tosequentially energize fuel injectors in the system in synchronism withthe demand of the internal combustion engine. The mechanism thusillustrated and described is particu larly applicable to individualinjector actuation, however the mechanism may be modified for multiplegroup actuation by the proper positioning and controlling of the lightactuated switching members.

We claim:

1. In a fuel injection system for an internal combustion engine, a lightactuated sequential switching mechanism for sequentially activating thefuel injectors, said mechanism comprising:

a shaft coupled for rotation with the distributor timing shaft of aninternal combustion engine;

a member having a pair of spaced broadside surfaces, one broadsidesurface attached to said shaft at the end opposite the coupling end,said member mounted for rotation with said shaft;

a source of light energy axially spaced from the end of said shaft anddirected toward the other broadside surface of said member;

a fiber optic bundle mounted for support between said pair of broadsidesurfaces having one end adapted for receiving energy from said source oflight opposite said other broadside surface and for conducting saidreceived light energy to the one broadside surface; and

a plurality of light actuated switching members equal in number to thenumber of injectors and respectively electrically connected in circuitto the injectors, said members positioned in a circumferential spacedapart relationship about said shaft, said switching members spaced fromsaid one broadside surface and each positioned to receive light energyfrom the other end of said bundle as said shaft rotates for switchingsaid members from one circuit condition to a second circuit condition.

2. In the light actuated sequential switching mechanism according toclaim I wherein said source of light energy is a light emitting diodeenergized from the activation of the ignition system for the internalcombustion engine.

3. In the light actuated sequential switching mechanism according toclaim 1 wherein said fiber optic bundle has said ends mounted flush withsaid one and said other broadside surfaces repsectively.

4. In the light actuated sequential switching mechanism according toclaim 1 wherein said light actuated switching members arephototransistors.

5. In the light actuated sequential switching mechanism according toclaim 1 wherein said fiber optic bundle has said one end positioned atthe axis of rotation of said one broadside surface and extends betweensaid pair of spaced broadside surfaces to said other broadside surfacenear the periphery thereof.

6. In the light actuated sequential switching mechanism according toclaim 1 wherein said source of radiant energy comprises at least twoindividual sources electrically connected in circuit for redundantenergi zation.

7. In a fuel injection system for an internal combustion engine, a lightactuated sequential switching mechanism for sequentially activating thefuel injectors, said mechanism comprising:

a shaft coupled for rotation with the distributor timing shaft of aninternal combustion engine;

a member having a pair of spaced apart broadside surfaces, one broadsidesurface attached at its center of rotation to said shaft at the endopposite the coupling end, said member mounted for rotation with saidshaft;

a source of radiant energy axially spaced from the end of said shaft andaxially aligned therewith, said source of energy directed toward theother broadside surface of said member;

at least two fiber optic bundles supported between said pair ofbroadside surfaces, each of said bundles having one end thereofpositioned at the center of rotation of the other broadside surface andadapted for receiving energy from said source of radiant energy, theother end of each of said bundles radially extending away therefrom andangularly spaced apart N degrees, each of said bundles formed fortermination at said one broadside surface so as to transmit the radiantenergy received at said one end; and

a plurality of radiant energy activated switching members equal innumber to the total number of injectors divided by the total number offiber optic bundles, said switching members equiangularly positioned ina circumferential spaced apart relationship about said shaft and spacedfrom the path of rotation of said bundles, said switching membersresponsive to the radiant energy emitted by said bundles for actuationand initiating the activation of one of said injectors.

8. In the light actuated sequential switching mechanism according toclaim 7 wherein said N degree angularly spacing between said fiber opticbundles is equal to an odd multiple of the quotient derived by dividing360 by the number of injectors.

9. In the light actuated sequential switching mechanism according toclaim 7 wherein said source of radiant energy comprises at least twoindividual sources electrically connected in circuit for redundantenergization.

10. In the light actuated sequential switching mechanism according toclaim 7 wherein said source of radiant energy is adapted to be energizedfrom the activation of the ignition system for the internal combustionengine.

1. In a fuel injection system for an internal combustion engine, a lightactuated sequential switching mechanism for sequentially activating thefuel injectors, said mechanism comprising: a shaft coupled for rotationwith the distributor tiMing shaft of an internal combustion engine; amember having a pair of spaced broadside surfaces, one broadside surfaceattached to said shaft at the end opposite the coupling end, said membermounted for rotation with said shaft; a source of light energy axiallyspaced from the end of said shaft and directed toward the otherbroadside surface of said member; a fiber optic bundle mounted forsupport between said pair of broadside surfaces having one end adaptedfor receiving energy from said source of light opposite said otherbroadside surface and for conducting said received light energy to theone broadside surface; and a plurality of light actuated switchingmembers equal in number to the number of injectors and respectivelyelectrically connected in circuit to the injectors, said memberspositioned in a circumferential spaced apart relationship about saidshaft, said switching members spaced from said one broadside surface andeach positioned to receive light energy from the other end of saidbundle as said shaft rotates for switching said members from one circuitcondition to a second circuit condition.
 2. In the light actuatedsequential switching mechanism according to claim 1 wherein said sourceof light energy is a light emitting diode energized from the activationof the ignition system for the internal combustion engine.
 3. In thelight actuated sequential switching mechanism according to claim 1wherein said fiber optic bundle has said ends mounted flush with saidone and said other broadside surfaces repsectively.
 4. In the lightactuated sequential switching mechanism according to claim 1 whereinsaid light actuated switching members are phototransistors.
 5. In thelight actuated sequential switching mechanism according to claim 1wherein said fiber optic bundle has said one end positioned at the axisof rotation of said one broadside surface and extends between said pairof spaced broadside surfaces to said other broadside surface near theperiphery thereof.
 6. In the light actuated sequential switchingmechanism according to claim 1 wherein said source of radiant energycomprises at least two individual sources electrically connected incircuit for redundant energization.
 7. In a fuel injection system for aninternal combustion engine, a light actuated sequential switchingmechanism for sequentially activating the fuel injectors, said mechanismcomprising: a shaft coupled for rotation with the distributor timingshaft of an internal combustion engine; a member having a pair of spacedapart broadside surfaces, one broadside surface attached at its centerof rotation to said shaft at the end opposite the coupling end, saidmember mounted for rotation with said shaft; a source of radiant energyaxially spaced from the end of said shaft and axially aligned therewith,said source of energy directed toward the other broadside surface ofsaid member; at least two fiber optic bundles supported between saidpair of broadside surfaces, each of said bundles having one end thereofpositioned at the center of rotation of the other broadside surface andadapted for receiving energy from said source of radiant energy, theother end of each of said bundles radially extending away therefrom andangularly spaced apart N degrees, each of said bundles formed fortermination at said one broadside surface so as to transmit the radiantenergy received at said one end; and a plurality of radiant energyactivated switching members equal in number to the total number ofinjectors divided by the total number of fiber optic bundles, saidswitching members equiangularly positioned in a circumferential spacedapart relationship about said shaft and spaced from the path of rotationof said bundles, said switching members responsive to the radiant energyemitted by said bundles for actuation and initiating the activation ofone of said injectors.
 8. In the light actuated sequential switchingmechanism according to claim 7 Wherein said N degree angularly spacingbetween said fiber optic bundles is equal to an odd multiple of thequotient derived by dividing 360* by the number of injectors.
 9. In thelight actuated sequential switching mechanism according to claim 7wherein said source of radiant energy comprises at least two individualsources electrically connected in circuit for redundant energization.10. In the light actuated sequential switching mechanism according toclaim 7 wherein said source of radiant energy is adapted to be energizedfrom the activation of the ignition system for the internal combustionengine.